pom文件头报错
1.导入maven文件，经常遇到表头出错问题。报错：Failure to transfer org.apache.maven.shared:maven-filtering:pom:1.0-beta-2 from https://repo.maven.apache.org/maven2 was cached in the local repository, resolution will
not be reattempted until the update interval of central has elapsed or updates are forced. Original error: Could not transfer artifact org.apache.maven.shared:maven-
filtering:pom:1.0-beta-2 from/to central (https://repo.maven.apache.org/maven2): The operation was cancelled.
其大致原因是org.apache.maven.shared:maven-filtering:pom已经存在了，而且不能被强制更新了。
怎么将其更新呢？
首先根据org.apache.maven.shared:maven-filtering:pom:1.0-beta-2这个目录在本地仓库中删除对应文件夹下的.lastUpdated后缀名的文件。
从新更新maven工程，就行了。
https://blog.csdn.net/qy20115549/article/details/52890026
--------------maven手动导入maven：https://blog.csdn.net/hueason/article/details/73676667